Dream Theater called it "Constant Motion" and then more or less dared you to prove them wrong. Spoiler: your picking hand really will be in constant motion — mostly out of pure panic — while your foot tries to remember where beat one used to live.
This clip is Riff #7 from Dream Theater's "Constant Motion", the band's most gleefully Metallica-flavoured thrash moment: a palm-muted, alternate-picked slab of prog-metal that rewards tight rhythm and punishes the exact second your wrist gets lazy. PDF and Guitar Pro downloads are there so you can suffer accurately.
How the Constant Motion riff actually works
The whole thing lives on relentless alternate picking glued to aggressive palm muting. Petrucci isn't doing anything harmonically outrageous here — it's mostly low-string chugging with a few chromatic steps for menace — so the difficulty is roughly 90% right-hand stamina and 10% not tensing up. The trick: anchor the motion in your wrist, keep the pick angle shallow, and let the palm mute do the articulation instead of hammering the strings harder.
Concrete takeaway: park the metronome way below your ego — think 60% of target tempo — and only bump it up after ten clean reps in a row. Speed is a byproduct of relaxation, not effort. If your forearm is on fire, you're gripping the pick like it insulted your mother, and the notes will show it.
Play it slow, play it clean, and one day it'll genuinely sound like constant motion instead of constant apology. Want the tab and my slowed-down breakdown? It's all waiting over on my Patreon.